Synthesis and Crystal Structure of a New Organic-Inorganic Hybrid Compound: Tris(1,8-diammoniumoctane)bis(tetrachlorocobaltate) dichloride

Abstract

Self assembling perovskite-type organic-inorganic hybrids have been the focus of a number of investigations in recent years. Combining the characteristics of the organic and inorganic components offers an opportunity to incorporate useful properties, and thus providing access to a vast area of complex, multifunctional materials. 1 Fascination with these materials is generated by their interesting structural, magnetic, electrical, optical and chemical properties.Compounds having the general formula (NH3(CH2)nNH3)MX4 with X = Br, Cl, I and M = metal are known to crystallize in a layer structure. 2 These hybrid materials can be classified into two groups, based on the nature of the interface between the organic and inorganic entities; in a first group organic and inorganic compounds are linked only by weak bonds (hydrogen or van der-Waals bonds), while in a second group the two entities are linked together through strong chemical (either covalent or ionic) bonds. It has been shown that the structure of the MX4 units can vary considerably, ranging from isolated molecules (0D) 3 to extended chains (1D) 4 and up to two 5 or three-dimensional 6 networks.In this article we report on a new 0-dimensional compound that contains alkyl-chain diammonium 1,8-diammoniumoctane (abbreviated DAO), [CoCl4] 2-(abbreviated TCC) tetrahedral and uncoordinated chloride ions, connected by hydrogen bonds. The crystal structure was determinated by X-ray diffraction (XRD).Crystals of the title compound suitable for single-crystal X-ray diffraction were prepared as follows: CoCl2·6H2O (0.36 g, 1.5 mmol) was dissolved in an aqueous solution of HCl (37%); 1,8-diaminooctane (0.22 g, 1.5 mmol) was dissolved in 10 ml of distilled water/ethanol (1:1 v/v). The two solutions were then Fig. 1 Asymmetric unit of DAOTCC, with atom labels and 50% probability displacement ellipsoids for non-H atoms.

Two-Dimensional Halide Perovskites Incorporating Straight Chain Symmetric Diammonium Ions, (NH3CmH2mNH3)(CH3NH3)n−1PbnI3n+1 (m = 4–9; n = 1–4)

“…Because of this, the symmetry needs to be lowered to the monoclinic space group of Cc for even n -members and Pc for odd n -members so that the organic atoms can be independently refined in three dimensions, resulting in conformations of lower energy (Figure a). The lower symmetry allows for more degrees of freedom for the diammonium cations, and this results in the folding of the carbon-chain which, arguably, is a preferable conformation to the expanded straight carbon-chain observed in other systems (Figure c) . The folding of the diammonium cations leads to a decrease in the interlayer spacing (compared to a straight chain) so that a monolayer of eight-carbon-chain diammonium cations is roughly equivalent in width to a bilayer of four-carbon-chain monoammonium cations (Figure d).…”

“…The lower symmetry allows for more degrees of freedom for the diammonium cations and this results in the folding of the carbon chain which, arguably, is a preferable conformation to the expanded straight carbon chain observed in other systems (Figure 2c). 54 The folding of the diammonium cations, leads to a decrease in the interlayer spacing (compared to a straight chain) so that a monolayer of eight-carbon-chain diammonium cations is roughly equivalent in width to a bilayer of four-carbon-chain monoammonium cations (Figure 2d). The decrease in symmetry is statistically justified by the Hamilton significance test.…”

Crystal structure of octane-1,8-diaminium 4,4′-(diazene-1,2-diyl)dibenzoate monohydrate

“…A search in the Cambridge Structural Database (Version 5.39 with one update; Groom et al, 2016) returned 48 entries for octane-1,8-diaminium compounds. These include simple halide salts (Brisson & Brisse, 1984;van Blerk & Kruger, 2007;van Megen & Reiss, 2013); metal halide salts (Kessentini et al, 2011) comprising lead halide complexes (Lemmerer & Billing, 2012;Smith et al, 2017), and more complex systems where the diaminium cations are encapsulated in a macrocycle (Kim et al, 2009;Yu et al, 2014). A similar search for 4,4 0 -azinodibenzoic acid and its salts returned 43 entries, including the structure of the simple acid (Yu & Liu, 2009).…”